Transport regimes of a split gate superconducting quantum point contact in the two-dimensional LaAlO<sub>3</sub>/SrTiO<sub>3</sub> superfluid.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 29892080.
- Also identified by DOI 10.1038/s41467-018-04657-z and PMC identifier 5995834.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
One of the hallmark experiments of quantum transport is the observation of the quantized resistance in a point contact in GaAs/AlGaAs heterostructures. Being formed with split gate technology, these structures represent in an ideal manner equilibrium reservoirs which are connected only through a few electron mode channel. It has been a long standing goal to achieve similar experimental conditions also in superconductors. Here we demonstrate the formation of a superconducting quantum point contact (SQPC) with split gate technology in a two-dimensional superconductor, utilizing the unique gate tunability of the superfluid at the LaAlO<sub>3</sub>/SrTiO<sub>3</sub> interface. When the constriction is tuned through the action of metallic split gates we identify three regimes of transport: First, SQPC for which the supercurrent is carried only by a few quantum transport channels. Second, superconducting island strongly coupled to the equilibrium reservoirs. Third, charge island with a discrete spectrum weakly coupled to the reservoirs.